ath9k_hw: clean up tx power handling

The code for handling various restrictions concerning regulatory limits,
antenna gain, etc. is very convoluted and duplicated across various
EEPROM parsing implementations, making it hard to review.

This patch partially cleans up the mess by unifying regulatory limit
handling in one function and simplifying handling of antenna gain.
It also removes unused transmit power scaling arrays from the EEPROM code,
which belonged to an unimplemented API that isn't supposed to be in
the driver anyway.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 6 insertions, 27 deletions

diff --git a/drivers/net/wireless/ath/ath9k/eeprom_9287.c b/drivers/net/wireless/ath/ath9k/eeprom_9287.c
index 6698b722b604..90d771fa2dea 100644
--- a/drivers/net/wireless/ath/ath9k/eeprom_9287.c
+++ b/drivers/net/wireless/ath/ath9k/eeprom_9287.c
@@ -336,6 +336,9 @@ static u32 ath9k_hw_ar9287_get_eeprom(struct ath_hw *ah,
                         return pBase->tempSensSlopePalOn;
                 else
                         return 0;
+        case EEP_ANTENNA_GAIN_2G:
+                return max_t(u8, pModal->antennaGainCh[0],
+                                 pModal->antennaGainCh[1]);
         default:
                 return 0;
         }
@@ -554,8 +557,7 @@ static void ath9k_hw_set_ar9287_power_per_rate_table(struct ath_hw *ah,
                                                      struct ath9k_channel *chan,
                                                      int16_t *ratesArray,
                                                      u16 cfgCtl,
-                                                     u16 AntennaReduction,
-                                                     u16 twiceMaxRegulatoryPower,
+                                                     u16 antenna_reduction,
                                                      u16 powerLimit)
 {
 #define CMP_CTL \
@@ -569,12 +571,8 @@ static void ath9k_hw_set_ar9287_power_per_rate_table(struct ath_hw *ah,
 #define REDUCE_SCALED_POWER_BY_TWO_CHAIN     6
 #define REDUCE_SCALED_POWER_BY_THREE_CHAIN   10
 
-        struct ath_regulatory *regulatory = ath9k_hw_regulatory(ah);
         u16 twiceMaxEdgePower = MAX_RATE_POWER;
-        static const u16 tpScaleReductionTable[5] =
-                { 0, 3, 6, 9, MAX_RATE_POWER };
         int i;
-        int16_t twiceLargestAntenna;
         struct cal_ctl_data_ar9287 *rep;
         struct cal_target_power_leg targetPowerOfdm = {0, {0, 0, 0, 0} },
                                     targetPowerCck = {0, {0, 0, 0, 0} };
@@ -582,7 +580,7 @@ static void ath9k_hw_set_ar9287_power_per_rate_table(struct ath_hw *ah,
                                     targetPowerCckExt = {0, {0, 0, 0, 0} };
         struct cal_target_power_ht targetPowerHt20,
                                     targetPowerHt40 = {0, {0, 0, 0, 0} };
-        u16 scaledPower = 0, minCtlPower, maxRegAllowedPower;
+        u16 scaledPower = 0, minCtlPower;
         static const u16 ctlModesFor11g[] = {
                 CTL_11B, CTL_11G, CTL_2GHT20,
                 CTL_11B_EXT, CTL_11G_EXT, CTL_2GHT40
@@ -597,24 +595,7 @@ static void ath9k_hw_set_ar9287_power_per_rate_table(struct ath_hw *ah,
         tx_chainmask = ah->txchainmask;
 
         ath9k_hw_get_channel_centers(ah, chan, &centers);
-
-        /* Compute TxPower reduction due to Antenna Gain */
-        twiceLargestAntenna = max(pEepData->modalHeader.antennaGainCh[0],
-                                  pEepData->modalHeader.antennaGainCh[1]);
-        twiceLargestAntenna = (int16_t)min((AntennaReduction) -
-                                           twiceLargestAntenna, 0);
-
-        /*
-         * scaledPower is the minimum of the user input power level
-         * and the regulatory allowed power level.
-         */
-        maxRegAllowedPower = twiceMaxRegulatoryPower + twiceLargestAntenna;
-
-        if (regulatory->tp_scale != ATH9K_TP_SCALE_MAX)
-                maxRegAllowedPower -=
-                        (tpScaleReductionTable[(regulatory->tp_scale)] * 2);
-
-        scaledPower = min(powerLimit, maxRegAllowedPower);
+        scaledPower = powerLimit - antenna_reduction;
 
         /*
          * Reduce scaled Power by number of chains active
@@ -815,7 +796,6 @@ static void ath9k_hw_set_ar9287_power_per_rate_table(struct ath_hw *ah,
 static void ath9k_hw_ar9287_set_txpower(struct ath_hw *ah,
                                         struct ath9k_channel *chan, u16 cfgCtl,
                                         u8 twiceAntennaReduction,
-                                        u8 twiceMaxRegulatoryPower,
                                         u8 powerLimit, bool test)
 {
         struct ath_regulatory *regulatory = ath9k_hw_regulatory(ah);
@@ -834,7 +814,6 @@ static void ath9k_hw_ar9287_set_txpower(struct ath_hw *ah,
         ath9k_hw_set_ar9287_power_per_rate_table(ah, chan,
                                                  &ratesArray[0], cfgCtl,
                                                  twiceAntennaReduction,
-                                                 twiceMaxRegulatoryPower,
                                                  powerLimit);
 
         ath9k_hw_set_ar9287_power_cal_table(ah, chan);